Stop referring to grizzly

I am pretty sure that won't even work.

Also fix tiny typo in the faq

Change-Id: Ie2e5640b8d4214a271d5af3b652b1a18db010b61
diff --git a/README.md b/README.md
index 40060a7..206ffe0 100644
--- a/README.md
+++ b/README.md
@@ -25,9 +25,9 @@
 The DevStack master branch generally points to trunk versions of OpenStack
 components.  For older, stable versions, look for branches named
 stable/[release] in the DevStack repo.  For example, you can do the
-following to create a grizzly OpenStack cloud:
+following to create a juno OpenStack cloud:
 
-    git checkout stable/grizzly
+    git checkout stable/juno
     ./stack.sh
 
 You can also pick specific OpenStack project releases by setting the appropriate